Apparatus for generating undamped electric oscillations.



S. EISENSTEIN. v APPARATUS FOR GENERATING UNDAMPED ELECTRIC OSOILLATIONS. APPLICATION FILED SEPT. 5, 1907.

950,Q57, Patented Feb. 22,1910,

i A HEY.

. ment for a single-phase alternating current,

SIMON EISENSTEIN, OF KIEW, RUSSIA.

AP PABATUS FOR GENERATING UNDAMPED ELECTRIC OSCILLATIONS.

Specification of Letters Patent.

Patented Feb. 22, 1910.

Application filed September 5, 1907. Serial No. 391,477.

'lb all whom it may concern:

Be it known that I, SIMON Ersnrzsrmme subject of the Czar of Russia, residing 1n Kiew, in said Empire of Russia, have invented certain new and useful Improvements in Apparatus for Generating lindalnped Electric Oscillations, of which the following is a specification.

Repeated tests made with undamped oscuits have shown that it is necessary when such oscillations are to be kept up for a considerable'length of time to cool the positive electrode of the are used for the same. Heretofore this electrode was nrade from metal and artificially cooled by ater when currents of great strength are 'used.

The object of the invention is to use sevother can be employed for the formation of the are; one only being in action, while in the meantime the other can be cooled either naturally or artificially, so that the two electrodes taken together are subjected to a considerably diminished heating action than heretofore. As exciting current for the are l a sn'igle-phase or multiphase alternating current can be used.

In the accompanylng drawing, Figure 1 represents a diagram showing the arrangeand Fig. 2 is a diagram showing the arrangementin connection with a multiphase alternating current. 1

Similar reference characters indicate the same arts in both figures of the drawing' Re erring to the drawing, 1 represents the negative electrode of an electric light are and 2 and 3 are positive electrodes for the arc tobe formed, which electrodes are preferably made oi metal of great heat conductivity, and which may when necessary be cooled by artificial means. The positive electrodes 2 and 3 are connected with the ends of a transformer 4, or choking coil, while the negative electrode 1 connected through a choking coil 1* with the center of the transformer or choking coil 4. The alternating current is delivered from a suitable source S. It is well known that by using alternating currents of low frequency, of about -60 periods, an arc can be formed between two metallic electrodes with considerable ditiiculty, while with metal and carbon electrodes an arc is formed more easily, especially when the metal forms the positive electrode and the carbon the negative electrode, and 15 only extinguished in case the numnuun strength of the current is reached.

reasonthat the arc can be formed more easily between one of the electrodes, which is in a certain moment positive, and the ncgative electrode, than between two metallic cillations by using Duddell oscillatory cirt electrodes, of which one is positive and the other negative, though the tension between the negatlve electrode and one of the positive electrodes is onlv half as great as between the.

two metallic electrodes. According to the polar direction of the alternating current, the arc is formed either between the negative electrode 1 and the electrode 2, or the former and the electrode 3, the are being formed in every case on the metallic electrodc, which therefore in every case is the positive one. This result is generally known and is used, for instance, in mercury vapor lamps for the changing of an alternating 1 current into a continuous current, so that further description of this feature is not necessary.

By the aid of the three electrodes 1, 2 and 3 the well known Duddell oscillatory circuit is formed, for which purpose the condensers (3 and 7 are used. These have the same size, but are connectcd in such a manner that only one at a time is called into action, according as the arc is formed between the negative electrode and the positive electrode 2 or between the former and the positive electrode 3. There are therefore, so to say, two oscillatory ctrcuil's' formed, which, however, possess the autotransi'ormcr b, from which, according to the well known manner, either directly or inductively, the air-conductor 9 and the earth to are controlled. Inasmuch as the electrodes 2 and 3, according to the polar direction of the alternating current, are alternately called into action, and therefore subjected only temporarily to heating, the heating cannot reach such a degree as when the same electrodes are heated constantly in the formation of the arc. It is therefore possiblethat in such an arrangement conditions are produced where the phenomenon of generating undamped oscillations can take place in the best and easiest manner. It is therefore possible to arrange, for instance, the electrodes in an atmosphere congases, in vacuum under insulating liquids,

- undamped oscillations as compared With the known process, has the advantage that it is easier to generate a current of high tension, which heretofore, by the use of a con tinuous current for this purpose, could not be possible under other conditions. As stated, the improved process can also be used by using as the exciting current a three-phase alternating current. An example of such an arrangement is shown in Fl 2. In this case 1 is a negative electrode an 11, 12 and 13 are three electrodes which alternately act as positive electrodes and Which-are also formed of metal. The electrodes 11, 12 and 13 are connected with the ends of a rotary transformer 4, While the negative electrode 1 is connected over the choking coil 1 with the center 5 of the transformer. According to the succession of the phases the arc is formed between the negative electrode and alternately one of the ositive electrodes 11, 12 and 1?).

Each of these positive electrodes is con- ,nectod over the condensers 14, 15 and 16 with an autotransfcrmer 8 and the latter is influenced in the Well known manner by the air-conductor 9 and earth 10. The condensers in this case have also an equal ca pacity.

Practical tests have clearly shown that the process described gives satisfactory results only when a single or multiphase current of low tensionis used. When an alter noting current of high tension is to be employed, the formation of the arc is interrupted and uiidaniped oscillations can not be generated. This disadvantage can be avoided When a mercury vapor lamp for changing the current that feeds the negative carbon is switched in, 'as, for instance, in Fig. 2, in the current which feeds the negative electrode. This arrangement can, however, be made also in such a manner that the mercury vapor lamp for making the current continuous (or other similar device) is switched into the conductors connected Withthe positive electrodes. Such device can also be applied to the ne ativc aswell as to the different positive feet current conductors. This permits the use not only of a current of higher tension, but has also the advantage that for the formation of the arc metallic electrodes can be used.

Having thus described my invention, I

claim as new and desire to secure by Let-- ters Patent:

1. In an apparatus for generating undamped electrical oscillations, an oscillating cxciter composed of a negative electrode, a

plurality of positive electrodes, an oscillatory circuit for each positive electrode, and

means for causing an arc to form alternately between the differentpositive electrodes and the negative electrode.

2.111 an apparatus for gcneratin undamped electrical oscillations, an oscil sting exciter composed of a single negative elec trode, a plurality of positive electrodes, a plurality of oscillatory circuits in a shunt corresponding to the number of positive electrodes, and means for causing to be formed light arcs alternately between the positive electrodes and the negative electrode. I

3. in an apparatus for generating undainped electrical oscillations, the combination of a negative electrode, a plurality of positive clectrodcs, a condenser connected to each positive electrode, means for establishing oscillations between said condenser and said negative electrode, and means for sup plying alternating current separately to said electrodes.

'4. in an apparatus for generating undamped electrical oscillations, the c0inbination of a negative electrode, a'plurality of positive electrodes, a plurality of condensers placcd one each in series with each of the positive electrodes, an induction-coil connected at one end to said negative electrode, means for connecting said condensers to said coil, and means for conducting alternating currents to each of said electrodes.

ln an apparatus for generating undamped electrical oscillations, the combina 'tion of an auto-transformer, a carbon electrode connected to one end of the auto-transformer, a plurality of metallic electrodes, 21

i condenser connected to each metallic electi'ode, the other side of each condenser being connected to the other end of said transformer, and means for supplying alternating electric current to said carbon electrode and alternately to said metallic electrodes.

6. In an apparatus for generating undamped electrical oscillations, the combination of an auto-transformer, a carbon electrode connecled to one end of the auto-transformer, a plurality of metallic electrodes, a condenser connected to each metallic electrode, the other side of each condenser being connected to the other end of said transformer, and an alternating-current generator having a neutral Wire connected to said carbon electrode and its branches connected respectively to said metallic electrodes.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two subscribing Witnesses. SIMON EISENSTEIN. Witnesses:

WoLonnL-in HAUPT, HENRY HAsrnn. 

